Safety showers typically utilize about 90 liters of water per minute for about 15-20 minutes. Due to safety concerns and local and national regulations, the temperature of this water must generally have a temperature within a strict temperature range (e.g., 15-40° C.) as the water exits the safety showers. For these reasons, safety showers can consume large quantities of water, and require significant amounts of energy to heat or cool the water, especially in regions where solar radiation can heat the water above 40° C., or where the ambient temperature can cool the water to temperatures below 10° C.
To maintain the water's temperature within the required range, electrically-operated heating or cooling mechanisms are normally required, which adds disproportionately to the cost of a safety shower system. An exemplary system is discussed in U.S. Pat. No. 4,084,270 to Kersten, Jr. However, without such electrically-operated heating or cooling mechanisms, the water's temperature exiting the safety showers can be uncomfortable, unlawful, and possibly dangerous, dissuading people from using the safety showers for the entirety of the suggested time period.
Although there are safety shower systems without electrically-operated heating or cooling mechanisms such as that described in U.S. Pat. No. 3,949,707, such systems are generally unable to maintain the water's temperature above 10° C. year-round. For example, U.S. Pat. No. 4,465,020 to Schafer discusses placing a portion of an insulated tank below the frost line, such that water in the bottom of the tank can be heated by the ground temperature. The heated water can then be circulated with the remaining water in the tank to prevent the water from freezing. However, Schafer's device is problematic because it contemplates only maintaining the temperature of the water above freezing (0° C.), and such temperatures can still be uncomfortably low and potentially hazardous for use in safety shower systems.
Various geothermal heating and cooling systems are also known in the art, such as the WaterFurnace™ (http://www.waterfurnace.com). However, such systems known to Applicants fail to contemplate maintaining a water buffer for a safety shower system at a temperature of between 15° C.-40° C.
Thus, there is still a need for safety shower systems and methods that utilize geothermal energy to maintain a temperature of water in a water buffer between 15° C.-40° C.